Which of the following processes are spontaneous?

a. the melting of ice cubes at −10 °C and 1 atm pressure

b. separating a mixture of N₂ and O₂ into two separate samples, one that is pure N₂ and one that is pure O₂

c. alignment of iron filings in a magnetic field

d. the reaction of hydrogen gas with oxygen gas to form water vapor at room temperature

e. the dissolution of HCl(g) in water to form concentrated hydrochloric acid

Video transcript

Hey everyone. So here it says, identify the phase change description that corresponds to a positive DELTA G. Remember if your delta G. Is positive, that means it's non spontaneous, meaning it doesn't occur under natural conditions. So here ice forming liquid water at a standard pressure and 4°C. Right? So ice solid ice going to liquid water. Remember water begins to melt once we get to 0°C and it starts climbing. So it makes sense that we would be going from ice to liquid water with a temperature of 4°C. So this would be spontaneous and therefore delta U. Will be negative, not positive. Next steam forming liquid water at standard pressure 150°C. Remember water starts to vaporize once we get to 100°C the temperature is even higher than that. So we should expect our water to stay in its gaseous phase. We won't expect steam to condense down into a liquid. This doesn't make sense. This does not occur naturally. Therefore it's non spontaneous and delta G will be positive. This would be our answer. So far, Liquid water forming steam at standard pressure 106°C. Here, the temperature is high enough that liquid water can be vaporized into gas. So this isn't um spontaneous And then liquid water forming ice at a standard pressure and negative 5°C. So the temperature is low enough that liquid water can solidify into ice. So this is possible here are answer would have to be option